Hi, I am looking to get a lens with an index of 1·67 for a frame with a base curve of 7 for single vision. However, I am having difficulty finding a reliable answer from several opticians that I have visited as to what product I should choose such that I will have no peripheral distortions. Apparently, everyone else’s product is either fake or won’t work except the current one that I am being shown at any given optical store.   From what I could gather from Nikon’s...